The biggest alert being raised by medical experts over Colorado’s permissive pot culture is the threat to youth, from the womb to lifelong effects.

A symposium Friday by the Colorado School of Public Health on “Marijuana and Public Health” covered topics as diverse as traffic safety and the chemistry of pot’s pungency and potency, but the gravest concerns appeared centered on the risks to children.

Pot use is only legal for those over 18, but the greater accessibility of pot in the state seems to have trickled down to greater exposure for children.

Pregnant women who use marijuana should know it easily passes through the placenta to the fetus, said Dr. Laura Borgelt, associate professor at the University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences and School of Medicine.

The American Academy of Pediatrics says that although THC, the main chemical compound in marijuana, crosses the placenta, the placenta does somewhat limit fetal exposure because fetal THC concentrations are lower than maternal concentrations. However, THC and metabolites do act on the fetus’ developing biological systems, alter uterine blood flow and alter maternal behavior. Marijuana has been shown to alter brain neurotransmitters and biochemistry.

The long-term effects, according to the academy, is that marijuana use by the pregnant woman has been associated with deficits in the child’s “problem-solving skills requiring sustained attention and visual memory, analysis and integration, and with subtle deficits in learning and memory.”

The academy strongly recommends mothers breastfeed infants exclusively for about six months, followed by continued breastfeeding as other foods are introduced for 1 year or longer. And the academy even says that maternal substance abuse does not always mean she shouldn’t breastfeed. Yet certain drugs that accumulate in human milk, such as cocaine and cannabis, do have a negative effect on the infant’s long-term neuro-behavioral development. In other words, a woman who uses cannabis shouldn’t breastfeed.

Dr. George Sam Wang of Children’s Hospital Colorado said the incidence of children ending up in hospital emergency rooms after ingesting marijuana has increased dramatically since legalization of medicinal pot here in 2009.

Adolescents who regularly use marijuana (20 days a month or more) are two to four times more likely to develop psychosis than adolescents who do not, said Dr. Paula Riggs, professor and director of the Division of Substance Dependence in the Department of Psychiatry at the CU School of Medicine.

Between the ages of 10 and the late 20s, Riggs said, young peoples’ brains are under construction, and THC is very disruptive.

And adolescents are at greater risk of becoming chronic users once they’ve tried cannabis, she said. While one of 11 adults who try pot progress to regular use, she said, one out of six adolescents who try it will become chronic users.

The rate of new lung cancer in the United States has declined, proof that anti-smoking campaigns work, the CDC said today.

A national study found that from 2005 to 2009, lung cancer rates went down 2.6 percent per year among men, from 87 to 78 cases per 100,000 men, and 1.1 percent per year among women, from 57 to 54 cases per 100,000 women.

The fastest decline was among adults 35 to 44 years old, and especially among men.

“These dramatic declines in the number of young adults with lung cancer show that tobacco prevention and control programs work – when they are applied,” CDC Director Tom Frieden said.

Lung cancer is the leading cause of cancer death and the second most commonly diagnosed cancer among U.S. men and women. Most cases are caused by cigarette smoking and secondhand smoke.

The study found lung cancer incidence decreased among men in all U.S. Census regions and 23 states, and decreased among women in the South and West and seven states. Rates were stable in all other states.

It was 50 years ago this month that the Surgeon General linked cigarette smoking to lung cancer, yet smoking remains the leading cause of preventable death and disease in this country. Millions of Americans have smoking-related diseases, and each day more than 2,100 youth and young adults become daily smokers, the CDC said.

Soon after our story describing the challenges for Colorado as hundreds of thousands of Medicaid patients seek newly available dental benefits in the coming year, the Colorado Health Institute has further sharpened the picture of what problem lie ahead.

We mentioned in our story that a handful of counties in Colorado have no dentist at all, and the CHI report gives us a map of those now-eight counties. But they add in another challenging layer, those counties whose only available dental care is at federally qualified health clinics. That care is certainly far better than none at all, but it is also limited, and the combined territories cover wide swaths of Colorado.

A new map shows wide gaps in dental care for lower income Coloradans and rural areas. Gray is no private dentist at all; orange means oral care is only available at a federally-funded clinic. (Colorado Health Institute)

Cultural differences may explain why some girls in minority groups and low-income families – who have a statistically higher risk of cervical cancer – are not getting the human papillomavirus or HPV vaccine, according to a new study from the University of Colorado School of Medicine and Children’s Hospital Colorado.

While English-speaking parents said they were concerned over the vaccine’s need and safety, Spanish-speaking parents said they feared the vaccine would encourage sexual activity and that health care providers failed to explain that they needed three shots to be fully immunized.

“The reasons low-income girls did not initiate or complete the HPV vaccination were strikingly different depending on whether their parents spoke English or Spanish” said study author Dr. Sean O’Leary, an investigator at the Children’s Outcomes Research Program, which is affiliated with Children’s Hospital. “This is a safe and effective vaccine. We are seeing huge declines in HPV infection rates in the U.S. overall and especially among those who have received the vaccine.”

The vaccine is given in three doses over six months. Overall, 33 percent of girls have had three shots while 28 percent of those below the poverty line received the injections, according to the Centers for Disease Control and Prevention (CDC).

HPV is the most commonly sexually transmitted infection in the U.S. with 75 percent of Americans infected at some point, O’Leary said. It is also a leading cause of cervical cancer in women and throat cancer in men.

The study’s researchers recommend that health care providers fully explain the need for the vaccines to their patients and he necessity of three shots.

“The HPV vaccine is one of the few tools we have that actually prevents cancer,” O’Leary said.

A baby is safer sleeping in a box than in an adult bed, according to health officials from Children’s Hospital Colorado.

Experts worried about babies displaced by Colorado flooding are warning parents not to put babies to sleep in a dangerous place. If there is no crib, pack-n-play or bassinet available, babies should be put to sleep on their backs in a box, officials said.

Sudden Unexpected Infant Death is linked to the deaths of more than 50 babies in Colorado each year, and one of the main causes is accidental suffocation from infants sleeping in unsafe places, including a couch or adult bed. The death rate by accidental suffocation in infants is increasing nationally.

Despite concerns about the dangers of growing obesity rates, Colorado was the third best state in the nation for rates of preventable deaths like heart disease, stroke and hypertension, and the rates continue a long decline, a new CDC analysis says.

So we’re not 49th in everything.

Colorado has done better than most states battling heart disease, but could do better (AP Photo)

Just over 2,000 people died of those heart and circulation problems in 2010 in Colorado, for a rate of about 39.9 deaths per 100,000 people. The rate in 2001 was 57 per 100,000, showing a decline of about 3.9 percent a year even as worries grew over the effects of an obesity “epidemic.”

A state summary of the CDC findings noted that death rates in Colorado vary widely by county, apparently affected heavily by poverty and education levels. Colorado had six of the 10 counties across the nation that reported the lowest preventable death rates, but some rural and lower-income counties are still very high.

Eagle County, home to skiers and well-educated retirees and higher employment, had 18.1 deaths per 100,000 from these diseases from 2008 to 2010. Bent County, with much higher poverty and a much lower percentage of people completing college, had a rate of 89.7 per 100,000.

State director of public health programs Joni Reynolds said in the statement that while Colorado shows well nationally, there is still plenty of work to be done by residents and medical leaders on fighting tobacco use, promoting exercise and eating better foods.

So how do we stack up against other states? The lowest was Minnesota at 36.3 deaths per 100,000, a few lower than Colorado. Must be the health care — certainly not explained by long winters and the proximity to the Wisconsin cheese-based diet. The worst was the District of Columbia, at 99.6 deaths per 100,000.

A massive national cancer study is opening its final enrollment period this week, giving Coloradans one last chance to be part of a process that in the past has produced some of medicine’s basic tenets.

The American Cancer Society wants to enroll up to half a million people in the new study, which follows on groundbreaking mass studies launched in earlier decades. The past studies helped establish such basic medical conclusions as the connection between tobacco use and cancer, and the dangers of obesity to American health.

Cancer Prevention Study-3 begins enrolling Wednesday in Longmont, and at other locations in Colorado through the end of September. Volunteers will need to make an appointment at their local signup center, complete a survey, have some measurements taken and give blood samples. They will take home a wide survey of lifestyle and behavior, then follow up every couple of years with another survey.

If you want to be part of the answer to the key question, “What causes cancer?”, here’s a list of signup locations (again, an appointment is required for these locations, so first go to www.cps3Colorado.org to find appointment phone numbers):

After the casino association weighed in, we got one last letter from anti-tobacco campaigners who wanted to pass on an amplification from the study’s author, Stan Glantz. The following comment by Glantz was forwarded by Bob Doyle of the Colorado Tobacco Education and Prevention Alliance:

“The Colorado Gaming Association, mimicking the tobacco industry’s longstanding practice of using out-of-context quotes, is ignoring the fundamental observation in our study that when everywhere but casinos were made smokefree there was a 20% drop in ambulance calls from everywhere but casinos AND that when casinos were required to go smokefree ambulance calls from casinos dropped 20% while not changing everywhere else.

“Moreover, the 20% reduction is about the same as well-documented reductions in hospital admissions for heart attacks, strokes, asthma and other medical emergencies that have been consistent observed around the world following implementation of strong smokefree laws. The fact that the available data did not allow us to determine how much of this drop was due to reductions in secondhand smoke and how much was due to less smoking in no way undermines the fundamental observation that ambulance calls dropped.”

Doyle also sent a previous study, referenced by Glantz, showing similar drops in emergent calls when smoking bans were extended in other areas besides casinos. Here’s a summary: A study “published in the July 2011 issue of the American Journal of Medicine, found heart attack admissions in Greeley dropped 27% during the 2 ½ years following the smoke-free law passed in 2003. Although smokers and non-smokers saw reductions in heart attack admissions, the decline was greater for smokers with a 56% reduction.”

We appreciate it when a quick blog post prompts a pointed and thoughtful response from people who are interested in that health topic, and the post about a smoking ban and ambulance calls to Colorado casinos had that effect.

Lois Rice of the Colorado gaming industry said the study, which purported to show a connection between an extension of the smoking ban to casino floors and a subsequent drop in ambulance calls in Gilpin County, could not factor in some important variables. I’ll simply print her whole letter to us here:

“It is important that some flaws with this study in Monday’s health blog be pointed out.

“While the Colorado Gaming Association respects the legislature’s decision to repeal the casinos’ exemption to the smoking ban in 2008, we would encourage readers of this study to be cautious of the results. Colorado’s casino smoking ban went into effect just as the nationwide recession took hold, resulting in a 17%-22% reduction in casino visitation during 2008-09. The study itself states that it did not account for several factors to determine a direct causal effect of the smoking ban to the reduction of ambulance calls in Gilpin County. Accordingly, the sheer reduction of casino visitation due to the economy and other factors probably resulted in the drop in ambulance calls. The study states that its failure to explore statistical data about the patients or their smoking status made it impossible “to differentiate events possibly related to smoking or secondhand smoke (e.g. cardiovascular, respiratory) from events not likely to be related.”

“We would encourage jurisdictions exploring the effect of smoking bans to include other empirical research in their analyses.”

Will abstaining from alcohol make you live longer? It kind of depends on why you don’t drink.

A new study from the University of Colorado-Boulder explores why non-drinkers have a higher mortality risk than people who are light drinkers, and it turns out it matters why they don’t drink.

Previous studies have found that the likelihood of dying increases the more people drink. Those studies also have found that people who choose not to drink at all have higher mortality rates than light drinkers, perhaps because light drinkers reduce their stress levels and risk of diseases. The latest CU study explored the reasons why people don’t drink and whether those could explain increased mortality risk.

Researchers found that people who never drink, often because of moral or religious reasons, had similar mortality rates to light drinkers. “So this idea that nondrinkers always have higher mortality than light drinkers isn’t true,” said sociology professor Richard Rogers, director of CU-Boulder’s Population Program in the Institute of Behavioral Science. “You can find some groups of nondrinkers who have similar mortality risks to light drinkers.”

The scientists also found that infrequent drinkers generally had a slightly higher mortality risk than light drinkers. Former drinkers, however, had the highest mortality risk of all nondrinkers. Former drinkers — including alcoholics — had a 38 percent higher mortality risk than light drinkers.

Drinking too much was clearly linked to higher mortality. People who drink between one and two drinks per day have a 9 percent higher mortality rate than light drinkers, while people who drink from two and three drinks per day have a 49 percent higher mortality. People who consume more than three drinks per day had a 58 percent higher mortality risk compared to light drinkers.

“I think the idea that drinking could be somewhat beneficial seems like it’s overstated,” Rogers said. “There may be other factors that lower mortality for light drinkers. It’s not just the act of drinking.”

Researchers relied on data collected in 1988 by the National Health Interview Survey regarding drinking habits of more than 41,000 people from across the country. The researchers knew which respondents died between 1988 and 2006. The study was published in last month’s issue of the journal “Population Research and Policy Review.” University of Colorado Denver researchers also worked on the study.

Electa Draper is the health writer for The Denver Post and has covered every news beat in a 22-year journalism career at three newspapers. She has a bachelor's degree in biology and a master's in journalism.